add caching back in

.gitignore

@@ -1,4 +1,5 @@
 /vendor
 /coverage
 /.phpunit.cache
-/composer.lock
+/composer.lock
+/tests/cache

src/TagEngine.php

@@ -3,6 +3,7 @@
 
 namespace LordSimal\CustomHtmlElements;
 
+use Exception;
 use LordSimal\CustomHtmlElements\Error\TagNotFoundException;
 use Spatie\StructureDiscoverer\Discover;
 
@@ -16,6 +17,8 @@ class TagEngine
     protected array $options = [
         'component_prefix' => 'c', // Prefix for custom tags
         'tag_directories' => [], // Location for tag extensions
+        'enable_cache' => false, // Enable caching
+        'cache_dir' => '', // Location for cache files
     ];
 
     /**
@@ -46,6 +49,18 @@ public function __construct(array $options = [])
         $prefix = $this->options['component_prefix'] ?? 'c';
         $this->regex = sprintf($this->regex, $prefix, $prefix, $prefix);
         $this->registerTags();
+
+        if ($this->options['enable_cache']) {
+            if (empty($this->options['cache_dir'])) {
+                throw new Exception('Please set a `cache_dir` config');
+            }
+            if (!is_dir($this->options['cache_dir'])) {
+                throw new Exception('Cache directory does not exist');
+            }
+            if (!is_writable($this->options['cache_dir'])) {
+                throw new Exception('Cache directory is not writable');
+            }
+        }
     }
 
     /**
@@ -148,6 +163,14 @@ protected function parseAttributes(string $attributesString): array
      */
     protected function renderComponent(string $componentName, array $attributes, string $innerContent = ''): string
     {
+        if ($this->options['enable_cache']) {
+            $cacheKey = md5($componentName . serialize($attributes) . $innerContent);
+            $cacheFile = $this->options['cache_dir'] . DIRECTORY_SEPARATOR . $cacheKey . '.html';
+            if (file_exists($cacheFile)) {
+                return file_get_contents($cacheFile);
+            }
+        }
+
         try {
             $class = TagRegistry::getTag(sprintf('%s-%s', $this->options['component_prefix'], $componentName));
             $tag = new $class($attributes, $innerContent);
@@ -160,6 +183,12 @@ protected function renderComponent(string $componentName, array $attributes, str
             $tag::$tag = $componentName;
         }
 
-        return $tag->render();
+        $html = $tag->render();
+
+        if ($this->options['enable_cache']) {
+            file_put_contents($cacheFile, $html);
+        }
+
+        return $html;
     }
 }

tests/TagEngine/CacheTest.php

@@ -0,0 +1,79 @@
+<?php
+declare(strict_types=1);
+
+namespace LordSimal\CustomHtmlElements\Test\TagEngine;
+
+use FilesystemIterator;
+use LordSimal\CustomHtmlElements\TagEngine;
+use PHPUnit\Framework\TestCase;
+use RecursiveDirectoryIterator;
+use RecursiveIteratorIterator;
+
+/**
+ * @see \LordSimal\CustomHtmlElements\TagEngine
+ */
+class CacheTest extends TestCase
+{
+    protected string $cacheDir = '';
+
+    protected TagEngine $tagEngine;
+
+    protected function setUp(): void
+    {
+        $this->cacheDir = dirname(__DIR__) . DIRECTORY_SEPARATOR . 'cache' . DIRECTORY_SEPARATOR;
+        if (!is_dir($this->cacheDir)) {
+            mkdir($this->cacheDir);
+        }
+        $this->tagEngine = new TagEngine([
+            'tag_directories' => [
+                dirname(__DIR__) . DIRECTORY_SEPARATOR . 'Tags' . DIRECTORY_SEPARATOR,
+                dirname(__DIR__) . DIRECTORY_SEPARATOR . 'plugins' . DIRECTORY_SEPARATOR,
+            ],
+            'enable_cache' => true,
+            'cache_dir' => dirname(__DIR__) . DIRECTORY_SEPARATOR . 'cache' . DIRECTORY_SEPARATOR,
+        ]);
+    }
+
+    protected function tearDown(): void
+    {
+        $files = new RecursiveIteratorIterator(
+            new RecursiveDirectoryIterator($this->cacheDir, FilesystemIterator::SKIP_DOTS),
+            RecursiveIteratorIterator::CHILD_FIRST
+        );
+
+        foreach ($files as $fileInfo) {
+            $todo = ($fileInfo->isDir() ? 'rmdir' : 'unlink');
+            $todo($fileInfo->getRealPath());
+        }
+
+        rmdir($this->cacheDir);
+    }
+
+    /**
+     * Test a tag with a simple attribute (non-self-closing)
+     *
+     * @return void
+     */
+    public function testCacheWillBeFilledAndRead(): void
+    {
+        $element = '<c-youtube src="RLdsCL4RDf8"></c-youtube>';
+        $result = $this->tagEngine->parse($element);
+        $expected = <<<HTML
+			<iframe width="560" height="315" 
+				src="https://www.youtube.com/embed/RLdsCL4RDf8" 
+				allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" 
+				allowfullscreen>
+			</iframe>
+HTML;
+        $this->assertSame($expected, $result);
+
+        $files = new RecursiveIteratorIterator(
+            new RecursiveDirectoryIterator($this->cacheDir, FilesystemIterator::SKIP_DOTS),
+            RecursiveIteratorIterator::CHILD_FIRST
+        );
+        $this->assertGreaterThan(0, iterator_count($files));
+
+        $result = $this->tagEngine->parse($element);
+        $this->assertSame($expected, $result);
+    }
+}